1. Field of the Invention
The present invention relates to a hard disk drives (HDDs). More particularly, the invention relates to a HDD using a method that improves a read hit ratio to data stored in a memory associated with the HDD.
This application claims priority to Korean Patent Application No. 10-2006-62206, filed on Jul. 3, 2006, the subject matter of which is hereby incorporated by reference.
2. Description of Related Art
Conventional HDDs are data storage devices adapted to record (write) data on and reproduce (read) data from magnetic recording medium generally referred to as a disk. HDDs are widely used as auxiliary data storage devices in computer systems because of the fast access time they provide to large quantities of stored data. During write operations, HDDs convert digital electric pulses into a fluctuating magnetic field in order to write data on the disk. During read operations, an induced magnetic field from the disk is converted into digital electric pulses. During both read and write operations, one or more magnetic head(s) moves across a disk surface to a target sector where data has been (or will be) written. The time required to move the magnetic head and/or the portion of the disk surface containing the target sector represents a significant portion of the overall delay required to read data from the disk. Minimizing this delay is an important HDD design consideration.
Recognizing the importance of minimizing the data access delay, it should be noted that there are often times where the magnetic head is properly positioned over a target track on the disk, but the disk requires some period of time to rotate the target sector under the magnetic head. This rotational movement time is part and parcel of the overall access delay and should be accounted for in any attempt to maximize the efficiency of read/write within the HDD.